using System;

using Org.BouncyCastle.Asn1;

namespace Org.BouncyCastle.Asn1.X509
{
	public class AttCertValidityPeriod
		: Asn1Encodable
	{
		private readonly DerGeneralizedTime	notBeforeTime;
		private readonly DerGeneralizedTime	notAfterTime;

		public static AttCertValidityPeriod GetInstance(
			object obj)
		{
			if (obj is AttCertValidityPeriod || obj == null)
			{
				return (AttCertValidityPeriod) obj;
			}

			if (obj is Asn1Sequence)
			{
				return new AttCertValidityPeriod((Asn1Sequence) obj);
			}

			throw new ArgumentException("unknown object in factory: " + obj.GetType().Name, "obj");
		}

		public static AttCertValidityPeriod GetInstance(
			Asn1TaggedObject	obj,
			bool				explicitly)
		{
			return GetInstance(Asn1Sequence.GetInstance(obj, explicitly));
		}

		private AttCertValidityPeriod(
			Asn1Sequence seq)
		{
			if (seq.Count != 2)
				throw new ArgumentException("Bad sequence size: " + seq.Count);

			notBeforeTime = DerGeneralizedTime.GetInstance(seq[0]);
			notAfterTime = DerGeneralizedTime.GetInstance(seq[1]);
		}

		public AttCertValidityPeriod(
			DerGeneralizedTime	notBeforeTime,
			DerGeneralizedTime	notAfterTime)
		{
			this.notBeforeTime = notBeforeTime;
			this.notAfterTime = notAfterTime;
		}

		public DerGeneralizedTime NotBeforeTime
		{
			get { return notBeforeTime; }
		}

		public DerGeneralizedTime NotAfterTime
		{
			get { return notAfterTime; }
		}

		/**
		 * Produce an object suitable for an Asn1OutputStream.
		 * <pre>
		 *  AttCertValidityPeriod  ::= Sequence {
		 *       notBeforeTime  GeneralizedTime,
		 *       notAfterTime   GeneralizedTime
		 *  }
		 * </pre>
		 */
		public override Asn1Object ToAsn1Object()
		{
			return new DerSequence(notBeforeTime, notAfterTime);
		}
	}
}
